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Got Bored.

The Library Project

I created a ChatLibrary that will contain the valid commands and a Message that will contain the parsing.

public enum Command
Login = 0,
PersonalMessage = 1,
ClientList = 2,
Conference = 3,
Logout = 4

public class Message
string strSender;
string strReceiver;
Command cmdMessageCommand;
string strMessageDetail;
public Message ()
public Message (byte [] rawMessage)
string strRawStringMessage = System.Text.Encoding.ASCII.GetString (rawMessage);
string [] strRawStringMessageArray = strRawStringMessage.Split(new char []{'|'});
this.strSender = strRawStringMessageArray[1];
this.strReceiver = strRawStringMessageArray[2];
this.cmdMessageCommand = (Command) Convert.ToInt32(strRawStringMessageArray[3]);
this.MessageDetail = strRawStringMessageArray[4];

public byte [] GetRawMessage ()
System.Text.StringBuilder sbMessage = new System.Text.StringBuilder ("John");
return System.Text.Encoding.ASCII.GetBytes(sbMessage.ToString());

The Server Project

I created a SocketServer that calls the TCPListener.Start() method

IPEndPoint endPoint = new IPEndPoint (ipaAddress, iPort);
listener = new TcpListener (endPoint);

Upon calling Listen, a new thread will be created that will listen for incoming clients

thrListenForClients = new Thread(new ThreadStart(ListenForClients));

The ListenForClients method will wait for connections and will assign the incoming socket to a new Client instance.

Client acceptClient = new Client();
acceptClient.Socket = listener.AcceptTcpClient();
listenForMessageDelegate = new ListenForMessageDelegate (ListenForMessages);
listenForMessageDelegate.BeginInvoke(acceptClient, new AsyncCallback(ListenForMessagesCallback), "Completed");

The Client, by the way is a class that contains a TCPClient, so we can keep track of our connections

public class Client {
string strName;
TcpClient tcpClient;
public Client()
public string Name
get{return strName;}
set{ this.strName = value;}
public TcpClient Socket
get{return tcpClient;}
set{ this.tcpClient = value;}
public void SendMessage (Message sendMessage)
NetworkStream stream = tcpClient.GetStream();
stream.Write(sendMessage.GetRawMessage() , 0, sendMessage.GetRawMessage().Length);

Our server is now ready to listen for incoming messages. To do this, we pass the client socket that we received, then make a loop. We use a NetworkStream to read the message

NetworkStream stream = client.Socket.GetStream();
byte [] bytAcceptMessage = new byte [1024];
stream.Read(bytAcceptMessage, 0, bytAcceptMessage.Length);
Message message = new ChatLibrary.Message(bytAcceptMessage);

Once we receive the message, we can do anything that we want

txtStatus.Text += "rn" + strDisplayMessageType + strWriteText.TrimStart(new char[]{'r','n'});

My SocketServer makes use of a few events that makes coding a little easier

public event ClientConnectedEventHandler ClientConnected;
public event ClientDisconnectingEventHandler ClientDisconnecting;
public event MessageReceivedEventHandler MessageReceived;

In my ServerForm codes, what I did was I kept a copy of each connected Client in a ClientCollection that inherits from System.Collections.CollectionBase. With this, I can iterate through the Clients.

The Client Project

The Client does basically the same thing. I created a ClientSocket that will create a TCPListener and call Connect()

IPEndPoint serverEndpoint = new IPEndPoint (ipaAddress , iPort);
tcpClient = new TcpClient ();
thrListenForMessages = new Thread (new ThreadStart(ListenForMessages));

What ListenForMessages will do is to loop with NetworkStream.Read()

stream = tcpClient.GetStream();
byte [] bytRawMessage = new byte [1024];
stream.Read(bytRawMessage, 0, bytRawMessage.Length);
ChatMessage receivedMessage = new ChatLibrary.Message (bytRawMessage);

Then we do the same process, create a Message using the received bytes.

Again, my goal is to create a YM/MSN - looking Instant Messenger, so I made two UI forms. The MessengerForm and the ClientWindow. The MessengerForm is the class that instantiates the ClientSocket and receives the messages. upon receiving a message, it calls the MessengerWindow that should display the text.

Note that I didn't do a regular instantiation. I called Invoke to be able to make my controls thread safe

this.Invoke(createNewClientDelegate, new object []{receivedMessage});


June 2006 : Initial Version


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About the Author


John lives in the Philippines with his family, working as a programmer. He used to program VB6 but is now... ummm... trying to learn C# .Net.

Occupation: Web Developer
Location: Philippines Philippines

  1. Blsmphhd 2008.12.14 04:30 신고


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